Floor assembly for motor vehicles

ABSTRACT

A floor assembly for motor vehicles comprising a skeleton frame of longitudinal and transverse supports, a layer of plastic material applied by a reaction injection molding process tightly covering each of said supports for interconnecting them to one another while leaving predetermined portions of said supports uncovered to facilitate installation of various motor vehicle elements, the plastic material also being disposed in sheet form horizontally between the supports to serve as a floor for the assembly.

United States Paten 1 11 1 3,746,387 Schwenk 1 July 17, 1973 1 FLOORASSEMBLY FOR MOTOR 3,331,627 7/1967 Schroder et al. 296/31 P VEHICLES3,565,480 2/1971 McCollum et al. 296/28 R 3,520,550 7/1970 Dysarz et al.280/106 R [75] Inventor: KurtSchwenk,'W0lfsburg, Germany FOREIGN PATENTSOR APPLICATIONS [73] Assigneez Volkswagenwerk AKG,Wolfsburg,

Germany Filed: June 16, 1971 Appl. No.: 153,640

Foreign Application Priority Data June 16, 1970 Germany P 20 29 665.5

US. Cl. 296/28 F, 52/309, 52/656, 264/45, 264/275, 280/106 R, 296/31 PInt. Cl B62d 21/02 Field of Search. 296/28 R, 28 F, 28 J, 296/31 R, 31P; 280/106 R; 52/309, 656;

References Cited UNITED STATES PATENTS Wessels, 280/106 R X Prochaska425/129 X 910,251 11/1962 Great Britain 296/31 P Primary Examiner-LeoFriaglia Assistant Examiner-Leslie .1 Paperner Attorney--GranvilleBrumbaugh et al.

[57] ABSTRACT A floor assembly for motor vehicles comprising a skeletonframe of longitudinal and transverse supports, a layer of plasticmaterial applied by a reaction injection molding process tightlycovering each of said supports for interconnecting them to one anotherwhile leaving 6 Claims, 5 Drawing Figures PAIENIE JUL 1 m1:

SHEEI 2 OF 2 Fig. 3

INVENTOR, saw :4:

1 FLOOR ASSEMBLY FOR MOTOR VEHICLES This invention relates to a floorassembly for motor vehicles which consists of a plastic material and askeleton for the frame composed of metal supports, the outwardlyextending longitudinal ones of which are disposed inwardly of theassembly.

In like constructions it has been known to provide a frame of stampedsheet metal frame sections, the longitudinal supports of which areencased by an inner and outer large surfaced shell made of plasticthereby leaving open gaps. The outer shell is attached to the innershell which is trough-shaped and is attached to, the longitudinalsupports in such a way as to provide a double floor (see German PatentNo. 1,275,372, for example). Such a construction is sufficiently stableand insures a good protection against corrosion, at least for thelongitudinal supports, but is expensive to produce since the floor mustbe prefabricated from several parts and must be attached separately tothe longitudinal supports. Connection of the plastic shells withthesupport frame, for example by means of links staggered with respect toone another, is both time consuming and'ex'pensive for large surfacedcasing parts. Besides, such a double floor in motor vehicles isapt toreverberate easily.

It has also been known, for a self-supporting floor assembly of porousplastic, to laminate metallic inserts onto the floor assembly for thepower supply lines for the motor, the driving mechanism, front and rearaxle and superstructures, before the curing. of the plastic mass, sothat the parts in the finished floor assembly may be easily mounted.Such construction, however,

requires the production of thick and expensive'walls.

The object of this invention is therefore to simplify the production ofsuch a construction assemblyso as to avoid reverberation problems and berelatively easy to construct.

i To this end, the floor assembly represents afinished construction unitwhichis obtained with the use of a reaction injection moldingprocess forthe produetion of theplastic floors, which'extends a's a single floorbetween metal supports and forms a plastic layer tightly enclosing alllongitudinal as well as all transverse supports of the frame skeleton ina manner whereby predetermined portions of the supports are leftuncovered to facilitate installation'of various motor vehicle elements.

Besidesprotecting all metal parts from corrosion, an advantage of sucharrangement is that the plastic flooring be produced and safely attachedto the skeleton in one work step by simply pouring the "skeleton frameinto the floor so that the plastic will flow entirely around themetalpartslt is therefore possible to carry out any other smaller ordetailed shaping of the floor assembly obtained in such manner. Thefinished floor assembly referred to herein includes the combination of ametal skeleton with a floor in such a manner as to improve upon theprocessing technique in this field. I The reaction injection moldingprocess used hereinincludes injection ofthe two components of apolyurethene duromertna'terial with the use of a mixing head into thehollow space of the mold. The mixture of raw material will startreacting after a relatively short time while expanding andsimultaneously developing pressure. At the same time a smooth, hardcover layer develops at the contact surfaces between plastic and mold,while the intermediate layer has the finely porous structure of hardfoam of the traditional type. The mold pressures developing during thereaction amount to about 1 kg/cm. The floor assembly produced accordingto this process is relatively light even in the case of fairly thickwalls of the actual floor.

Raised sections of the frame skeleton so produced provide a means forsimply mounting modern suspension unitsand provide a corrosionprotective layer for the upper mounting of such suspension unit togetherwith wheel boxes, thereby resulting in a further simplified design andcasting technique.

The metal skeleton will be effectively built on a base frame in whichintermediate longitudinal supports are disposed which project beyondthefront and rear of the frame, in pairs, in the manner of brackets and aredesigned as having hook-shaped free ends not covered with plastic.

The skeleton frame in its forward area is provided on both sides with asupport for the suspension of the front axle, which support is in thewall of the front wheel box and which is disposed at one end at thefront corner of the base frame. While it is shaped substantially as anarc in a vertical plane, it lies over the free end area of each frontmiddle longitudinal support and is provided at its top with a connectorpiece for the reception of the end of a suspension unit. Thisdevelopment of the front part of the floor assembly improves upon thesafety of the assembly and, because of its shape, can easily fold in thecase of a collision. Said supports are provided with a kneeor bendingplace to pennit collapsing in the event of a collision.

Also, the above-mentioned hook-shaped free ends are removably secured tothe longitudinal supports to facilitate easyrepair and replacementthereof.

FIG. 1 shows the motor vehicle floor assembly in accordance'with thepresent invention in a partially cut side view,

FIG. 2 shows one(symmetrical) half of the floor assembly of FIG. I inplan view 5; and s FIGS. 3 to '5 are sectional views taken respectivelyalong the lines IlI--III, IV-IV and Y-V of FIGSQZ and. 1, shown on aslightly enlargedscale.

Turning now tothe drawings wherein like reference characters refer tolike and corresponding parts throughout the several views, there isshown a floor assembly comprised of essentially twoparts, namelypaskeleton frame 1 and a plastic floor 2 produced by means of a reactioninjection molding process. Frame '1 includes a base frame 3 to which apair of innerlongitudinal rearsupports 5 are attached as shown in FIGS.1 and 2. Supports 4 are connected with and extend forwardly from amiddle transverse support 6 at their-rearsupport for the occupants ofthe rear seating compartment of the motor vehicle. The innerlongitudinal supports 4 and 5 have hook-shaped free ends 7 and 7',

which are removable. With the exception of the forward transversesupport I], which is made from tubing,

skeleton frame I consists of sheet metal stampings which form walls forthe frame's beam elements. Such walls may be arched inwardly or, as inFIG. 3, outwardly, in orderto adequately resist the pressure of thesubsequently produced plastic floor.

Inorder to create a safety body, front middle longitudinal supports 4are provided at A with a knee or a bending place beneath an elevatedsupport 8 which bridges support 4 with frame 3, the support 8 beingelevated in the manner shown in FIGS. 1 and 4 extending from the cornerof base frame 3 to the free end of longitudinal support 4. Support 8comprises struts made of tubing and a sheet metal connector 9 consistingof two sheet metal shells 9a and 9b (FIG. 4). In the event of acollision, supports 4 will bend at A and thereby serve to absorb theforce of the impact. In FIG. 2, it can be seen that connector 9 isslightly wider than struts 10 thereby making for easier production and ahigher degree of strength.

In order to further allow for buckling and further absorb the force ofan impact, the longitudinal supports 4 together with the forwardtransverse support 11 are disposed below base frame 3 and the rearlongitudinal supports 5 together with rear transverse support 12 aredisposed above base frame 3.

To facilitate easier attachment of the rear axle, the rear longitudinalsupports 5 are each provided with a perpendicularly disposed upwardlyprojecting sheet metal part 13.

The individual parts of skeleton frame 1 are firmly welded or gluedtogether and subsequently are placed in a correspondingly developedfoaming mold. After injection of the plastic mass, the latter flowsaround skeleton frame 1 on all sides so as to provide both aninterconnected assembly and a corrosion protective layer 14 while alsoconstituting a plastic floor 2, rear wheel boxes 16 and front wheelboxes (see FIG. 5). At those places where saturated metal parts fitagainst the skeleton frame, for example, at point B for the frontsuspension unit, at points C and D for the rear axle suspension and atend '7 and 7 of the longitudinal supports, the plastic is kept away fromthe supports in a known manner. It is also possible to combine parts ofthe skeleton frame together only provisionally by means of welding andto wrap the places of thrust with mats of glass fibers saturate d withsynthetic resin, which, upon curing, result in a sufficiently stiffconnection. In order to increase the strength of the plastic, glass matsmay be inserted into the foaming mold on which skeleton frame 1 isplaced. The attachment of a second layer of mats is accomplishedsubsequently. The mats also can be premolded.

Obviously many other modifications and variations aidof plasticmaterial, and a layer of plastic material tightly covering each of saidsupports while leaving predetermined pdrtions of siaid supportsuncovered to facilitate installation of various motor vehicle elements,said plastic material also being disposed in sheet form horizontallybetween said supports to serve as the only floor for the assembly, saidplastic material covering said supports and said plastic floor being asingle integrally formed member.

2. A floor assembly for motor vehicles comprising a skeleton frameincluding a base frame, longitudinal and transverse supports and wheelbox supports, all of said supports being firmly attached to each otherwithout the aid of plastic material, and a layer of plastic materialtightly covering each of said supports while leaving predeterminedportions of said supports uncovered to facilitate installation ofvarious motor vehicle elements and tightly covering each of said wheelbox supports, said plastic material also being disposed in sheet formover the wheel box supports so as to form wheel boxes and horizontallybetween said supports to serve as a single floor for the assemblyv 3.The floor assembly according to claim 2 wherein said wheel box supportsinclude a pair of front and a pair of rear wheel box supports, each ofsaid front wheel box supports forming a downwardly open are, said baseframe including lateral longitudinal supports and said skeleton frameincluding inner longitudinal supports having front and rear endsextending outwardly of the front and rear ends of said laterallongitudinal supports, respectively, an end of each said downwardlyextending are being disposed near said outward end of each said innerlongitudinal support and another end of each said downwardly extendingare being disposed near said front end of each said lateral longitudinalsupport, and each of said inner longitudinal supports having a kneeportion located near said front end to permit said inner longitudinalsupports to bend and thereby absorb the force of impact in the event ofa collision.

4. The floor assembly according to claim 2 wherein each of said supportsconsist of sheet metal stampings formed in the shape of box beams, saidbox beams having sides that are curved to resist the pressure of saidplastic floor.

5. The floor assembly according to claim 2 wherein the skeleton framealso includes inner longitudinal sup ports, the opposite ends of a pairof said inner longitudinal supports extend outwardly beyond the frontand rear ends of said base frame, the outer ends of said innerlongitudinal supports being hook-shaped and including said predeterminedportions uncovered by said plastic material.

6. The floor assembly according to claim 5 wherein said hook-shaped endsof said inner longitudinal supports are removably mounted thereon.

1. A floor assembly for motor vehicles comprising a skeleton framehaving a base frame and inner longitudinal supports, said base framehaving transverse supports and lateral longitudinal supports, all ofsaid supports being firmly attached to each other without the aid ofplastic material, and a layer of plastic material tightly covering eachof said supports while leaving predetermined portions of said supportsuncovered to facilitate installation of various motor vehicle elements,said plastic material also being disposed in sheet form horizontallybetween said supports to serve as the only floor for the assembly, saidplastic material covering said supports and said plastic floor being asingle integrally formed member.
 2. A floor assembly for motor vehiclescomprising a skeleton frame including a base frame, longitudinal andtransverse supports and wheel box supports, all of said supports beingfirmly attached to each other without the aid of plastic material, and alayer of plastic material tightly covering each of said supPorts whileleaving predetermined portions of said supports uncovered to facilitateinstallation of various motor vehicle elements and tightly covering eachof said wheel box supports, said plastic material also being disposed insheet form over the wheel box supports so as to form wheel boxes andhorizontally between said supports to serve as a single floor for theassembly.
 3. The floor assembly according to claim 2 wherein said wheelbox supports include a pair of front and a pair of rear wheel boxsupports, each of said front wheel box supports forming a downwardlyopen arc, said base frame including lateral longitudinal supports andsaid skeleton frame including inner longitudinal supports having frontand rear ends extending outwardly of the front and rear ends of saidlateral longitudinal supports, respectively, an end of each saiddownwardly extending arc being disposed near said outward end of eachsaid inner longitudinal support and another end of each said downwardlyextending arc being disposed near said front end of each said laterallongitudinal support, and each of said inner longitudinal supportshaving a knee portion located near said front end to permit said innerlongitudinal supports to bend and thereby absorb the force of impact inthe event of a collision.
 4. The floor assembly according to claim 2wherein each of said supports consist of sheet metal stampings formed inthe shape of box beams, said box beams having sides that are curved toresist the pressure of said plastic floor.
 5. The floor assemblyaccording to claim 2 wherein the skeleton frame also includes innerlongitudinal supports, the opposite ends of a pair of said innerlongitudinal supports extend outwardly beyond the front and rear ends ofsaid base frame, the outer ends of said inner longitudinal supportsbeing hook-shaped and including said predetermined portions uncovered bysaid plastic material.
 6. The floor assembly according to claim 5wherein said hook-shaped ends of said inner longitudinal supports areremovably mounted thereon.